Alfred



Patented June 1 7, 1924.

STATES PATENT OFFICE.

ALFRED ,CHARLES OTTO BOOK, OF BROOKLYN,.NEW YORK, ASSIGNOR TO FINGER- PRINT MACHINE CORPORATION,

A CORPORATION OF NEW YORK.

FINGERPRIN'T COMPOUNO) AND METHOD.

No Drawing.

To all whom it may concern:

Be it known that I, ALFRED CHARLES Or'ro Boon, a citizen of the United States of America, residing at Brooklyn, Kings Coun- 5 ty, New York, have invented new and useful Improvements in Fingerprint Compounds and Methods, of which the following is a specification.

This invention relates to substances for fixing the impression of finger prints and the like upon a paper or other surface.whereon a finger or other body has been impressed.

It is to be understood that while the substance forming the subject matter of the 1 present invention is especially useful in connection with the recording of finger prints, it ma beemployed in connection with other recor ing.

It has been found that a highly desirable manner of recording prints is to apply a powder to the impressed surface and afterward exposing it to, heat whereby the substance of the powder is caused to adhere to or become incorporated with the substance of the im ressed object.

I have ound that powdered resinous substances are well adapted for the treatment referred to and give an unusually well defined and permanent record.

Records of different colors may be desired and to this end, I may employ a powdered white resin, giving the desired color by aniline or in any other suitable we 'l he method employed in using the compound is to make t e impression of the nger upon a piece of paper, whereby the natural secretions of the finger or artificial adhesive material, such as oils applied there- Application filed June 1, 1921. Serial No. 474,195.

to, form lines upon the aper corresponding to the lines of the nger printed, the resinous powder is then applied to the impressed surface, the superfluous powder, that 15 to say that which does not adhere to the lines, is removed and the paper then bearing the powder adhering to the finger lines only is subjected to sufi'icient heat to cause the resin to soften or liquefy and sink into the body of the paper, when on becoming cool it is incorporated with and fixed therein.

As above stated the resinous powder may be white resin owdered and mixed or dyed with any suita le or desired color.

While the invention has been illustrated by a suitable composition it may be varied in various ways without departing from the spirit of the invention which is not therefore, limited to the precise proportions or ingredients specified. Similarly the method is not limited to the precise details recited, but may be varied therefrom without departing from the spirit of the invention.

What I claim is:

1. The method of recording a print which consists in making an impression, applying to the impression a compound containing resin and subjecting the powdered impression to heat.

2. The method of recording a print which consists-in making an impression, applying thereto a powdered compound containing powdered white resin and redetermined coloring material and su jecting the powdered impression to heat to fix the same. In testimony whereof I have signed this specification this 27th day of May, 1921.

ALFRED CHARLES OTTO BOCK. 

